Machine for making pneumatic tire covers or casings



Jan. 24, 1928. 1,657,267

c. MACBETH MACHINE FOR MAKING PNEUMATIC TIRE COVERS 0R CASINGS FiledJan.5. 1922 -2 Sheets-Sheet 1 i r 1291. 4 193 j 17 f Jam-24, 1928;1,657,267

c. MACBETH MACHINE FOR MAKING PNEUMATIC TIRE COVERS QR CASINGS FiledJams, 1922 2 Sheets-Sheet 2 WW W 1' 2 Patented Jan. 24, 1928.

UNITED STATES PATTI-INT OFFICE,

COLIN MAClBETH, OF BIRMINGHAM, ENGLAND, ASSIGNOR TO THE D'UNLOP RUBBERQOMPANKLIMITED, OE REGENTS PARK, LONDON, ENGLAND, A BRITISH G OMIAN Y.

' MACHINE FOR MAKING PNEUMATIC TIRE COVERS lOR CASINGS.

AppIication filed January :3, 1922, SeiialNo. 526,831 in Great BritainFebruary 4:, i921.

This invention relates to machines 'for making pneumatic tire covers orcasings (which machines are generally known as case making machines),and has particular reference 110 mechanism for rolling down the casingplies on the sides of a rotating core, comprising spinning :or rollingdown discs which are carried by arms pivoted on ai'eciprocating carriageor slide, the said arms and the discs carried thereby being adapted tobe moved into an inoperative position away from the sides of the core atthe end of the inward or forward movement (of the slide andto beretained in the inoperative position during the outward or returnmovement of theslide. a a 3 According to this invention, the means formoving the pivoted arms and the discs into the inoperative position areso constructed and ii-ranged as tOlDO'VB inwardor forward with theslide, when the discs effect the rolling down of the plies, and at theend of the inward or forward movement of the slide, the said meanspartake of a slight forward or rearward movement relatively to the slidein order to exert a thrust or pull on the saidpivoted arms to move thespinning down discs outwardly away from the sides ofithe core and retainthem in this positionwduring the outward or let urn mo-vement of theslide. The said :means for moving the pivoted arms and the :discs intothe inoperative position may be operated by thedrivin shat'twhichoperates the means for reciprocating the slide and may comprise aplungervor rods adapted to move forward with thesslide and to engage withprojections on the said pivotcd arms at the end of the forward move ment0]": the slide in order to move the arms and the discs into theinoperative position and retain them therein during the returnmovement-oi the slide. The reciprocation of the slide may be effected bymeans ofanosoillatory lever, and a similar leverymay be employed foractuating a. plunger which moves the pivoted arms and the discs into"the inoperative position. Alternatively cranks or eccentrics on arotating shaft-may be employed for reciprocating the slide and.

moving the pivoted arms into the inoperative position as hereinaitermore fully described. Means. may he provided for enahling the IiltEpOfinward or forward movement of the slide and the spinning down discs thevaried so that the discs may move atan initial high speed when laying orrollmg down the plies near the crown of the core, and at a slow speedwhen laying the plies over the bead heels. For this purposetheosci'llatory lever for reciprocating the shdemay he formed with acurved or cam slot in which a roller or pin eceentrically mounted on arevolving disc or the like is adapted to engage, the shape of this slotbeing such that the required variable speed ofanward movement isimparted to the slide and thezspinning clowndiscs. i

Inlorderthat the said invention maybe clearly understood and readilycarried into effect, the same will now be described more fully withreference ltO the accompanying drawings, in whicl1 i Fi ures ,1, 2 and 3are respectively a sec tiona .tront view, a plan, and sectional end viewof one construction of :the improved means in which oscillatory leversare used for efiectln-g the required movements.

Figures 4 and 15 late sectional front views of slightly modifiedconstruction.

Figure 6 "1s ;a chaaram [illustrating modi lied construction of theoscillatory lever for producing a variable speed of radial travel otthespinning down discs during the oper atlveistroke. p v Figure 7 is adiagram hereinafter lexplalned invconnect-ion with the-modified-n0llstruction of oscillatory lever illustrated in Figure 6. lI

-llligur,es :8 and 9 :ELI'B u'espectively a front view and 1a planshowing a construction in whichn crankshaft is used for effecting thereqniredanovem'ents.

Figures 10 and 11 are respectively a front View and aplan ofa furthermodification. it Figure 1-2 isle plan showingone mode of maintaininglthevidiscs :against the sides of the core.

Figure 13 isle sectional view including the oscillatory leverillustrated (in Figure 6,.

A represents a portion of the tire core which is supported on the rotaryspindle of the case making machine and A indicates a ply or pliesthereon. J3 B are the spinning down discs rotatably mounted ion bracketsB ,B .angularly movable on ,p'ins .13 B at the inner and forked @ends ofarms B B j a suitable rotarypart of the machine, carries In the exampleshownin Figures. 1 and 2, a revolving crank disc D operated from aneccentric hush having two portions D D of different diameters; thesmaller portion D fits in a longitudinal slot in alever D whose upperend is pivotally'connected to the aforesaid slide (3 and whose lower endhas an elongated slot in which ispositioned a pin D mounted in'the saidbase ort'rame C this connection at the lower end of the lever enablingthe latter to oscillate and move longitudinally onthe pin D due to therotary movement oi? the crank disc D and thus effect the reciprocationof the slide C. The said pin'D may beadjustable in a slot C in the saidbase in a direction parallel with the direction of movement of the slidethereby enabling the positions of the lever D and theslide Gto be variedto suit cores of different diameters, "The larger portionD of the saideccentric bush-fits in aslot in a second oscillatory lever D whose lowerend is mounted on the aforesaid pivot pin D whilst the upper 'end ofthis lever may carry a roller D which is adapted to engage with aplunger'D carried by-and slidably movable in a guide C fixed on theaforesaid slide. The plunger D carries at its forward end an adjustablehead D which at a predetermined moment is adapted to be but notrelatively thereto;

forced by the lever B? into contact with projections B on the pivotedarms B which carry the spinning down discs B. The larger portion D ofthe eccentricbush is so arranged as to cause the lever D to lag '45nected'directly or indirectly to the arms carrying the spinningdown'disc's sothatthe latter aremaintained against the sides of thecore. Figure 12 illustratesone construction in which the pivoted arms Bare prol vided with or have secured thereto projections or extensionsBTto which are connected by means of cables, chains or the like Gpassing around pulleys H tension-[springs J that are'securedto thecarriage or slide C. The tension springs J tend to pull the projectionsor extensions 13 in a. direction away from each other so that thepivoted arms 6 tend to move towards each other in order to maintain thediscs B in contact with the plies on the sides of the core. In additionto spring means for maintaining the discs in contact with the sides ofthe core additional pressure means may be provided whereby the pressurewith which thediscs bear on the plies is increased as the discs passover the heads, but this arrangement forms no part of thepresentinvention and is described in Patent No. 1,565,176. Upon the spinningdown discs B just passing the inner edges 01' the plies A" or the beadtoes thereon the lever l) in continuing its forward movement pushes theplunger D forward relatively to the slide C so that its adjustable headD engages with the projections B on the arms B carrying the spinningdown discs thus angularly moving the said arms B in such manner that thespinning down discs are moved away from the sides of the core; the

mechanism is so arranged that the lever D maintains the plunger head Din contact with the said projections B during the return'or outwardmovement of the slide so that the spinning down discs are held well awayfrom the plies on the core during the return or outward stroke. WVhenthe torwarr'l orfinward movement is about to take place again, the leverD is so controlled by the portion D oi. the eccentric hush engagingtherewith, that it no longer maintains the plunger head D in engagementwith the said projections B on the arms 13''" thus allowing the latterto assume the operative position in which the discs B make contactwiththe plies on the core.

Inthe modification shown in Figure l the lever D is formed at its upperend with a toothed segn'ient D in mesh with a toothed rack G on theunderside of the slide C, in this case the pivot pin D at the lower endof thislever fits in a round hole in the lever instead of an elongatedslot as in the foregoing example.

In the further modification shown in Fig ure 5 the upper end of thelever D is connected to the slide C through the intervention of a link Dand the upper end of the lever may also be connectedto the aforesaidplunger D by means of a link D 'lnslead of using an oscillatory lever Dwith straight slot as shown in Figures 1, 4 and 5' for effecting theinward or spinning down stroke of the discs B. the oscillatory lever Dmay he provided with a curved slot 1 in which the roller D works; bymeans 01": this curved slot it is possible. to vary the speed of radialtravel of the spinning down discs during the operative or spinning downstroke in such manner that the discs initially travel at a high speedover the casing from near the crown, the speed name? being graduallyreduced the discs travel over the sides oi? the casing until they aretravelling at a comparatively slow speed at the head heels whereifolding over the ply requires careful "operation in order to avoidcreasing at this point. The straightslot in the levers D shown inFigures 1, 4 and .5 does not permit of this speed variation andtherefore the speed of the discs during the inward radial movement ilSmainly determined by and has to conform with the slow speed required atthe beads. By using the lever D with the curved slot '1 the completeinward travel can he performed more quickly by reason of the initialrapid speed that can be imparted to the'disos.

Figure 7 shows a curve (1, 1), 0, def which the vertical ordinatesrepresent the radial velocity of the spinning down discs in relation tothe casing A of which one side or half is shown under the said curve. Itwill be observed from the curve that at the commencement of the strokeindicated at la the speed of [the discs increases very rapidly tomaximum at the point I) and then gradually decreases during the travelalong the sides of the casing until reaching the bead heel at c wherethe speed is very low to permit of the ply being folded over withoutcreasing, after which the speed increases to point- At the commencementof theinw-ard stroke, the lever D and the rollerD are i-n-th'epositionshown by dotted lines at the left in Figure 6 and as the roller inmoving round its circular path indicated by 41 leaves the curved face 1"of the curved slot the velocity rapidly increases to its maximum .asindicated at h in the diagram shown in Figure 7., when the face 1 of the\curved slot is ap; proximately at right angles to the path :of travelof the roller D. From tl-iispointthe velocity gradually decreases :asthe roller D moves down the face 1 and on reaching the position shown bydotted lines at the right in Figure 6 the face 1 is nearly tangential tothe circular path of travel of the roller when the velocity is very lowthis being at the point 0 on the aforesaid curve shown in Figure 7 wherethe spinning down discs are just travelling over the heads. After thisan increased velocity is produced by the roller D engaging with thecurved face 1". Thus the inward stroke is completed and the returnstroke is sinnlar to that obtained with the straight slotted lever shownin Figures 1, 4, 5, as the lower por tion of the curved slot 1' is madestraight. The type of lever shown in Figure 6 althongh particularlysuitable for beaded edge d'diiers or casings may he used with advantageon straight side covers as by retarding the speed of radial travel ofthe spinning down discs over the head a better consolidation of thelatter is effected whilst the complete cycle quickly than with thestraight slotted lever. Y

The example shown in Figures (8 y and 9 show a modification in "whichthe-aforesaid oscillatory levers D are not need; is this case thereciprocation of the slide (3 and the actuation of the arms 58 spinning:down discs B is effected sby means of :a three throw crank shaftrotatalb'ly mounted on a plate or frame 0 on which the slide i carryingthe arms B :s.upporting the spinning down .discs B is slidably. mounted.The C on which the crank shaft E is mounted is capable of adjustment onthe hase C" so that the whole spinning down mechanism can be readilyadjusted to suit cores of various diameters. The crank shaft E isrotated by a gear wheel E driven in any appropriate manner and by meansof a mod E connected to the medial crank of the shaft E it impart-sreciprocation to the slide C. The two outer cnan-ks oi the said shaft Eare connected means of pull rods E to projections B on the arms 13'carrying the spinning down discs and the angular positions of thecranksaa'e so .ar ranged that upon the .spimiing down discs completingthe inward or forward stroke, the outer cranks cause the pull rods E" toactand open vout the said arms B thus moving the spinning down discs outof contact with the sides of the core. The pull rods E may haveadjustable collars E which hear against the projections 13 on the saidarms In the further modification shown in Figures I0 and 11, instead ofusing a three throw crank shaft, there is employed a shaft F driven bygearing F and "having end cranks which through suitable rods Fconnectedto the slide C impart the reciproca tory movement to the slide'C. l The said shaft F has an intermediate eccentric F which may beconnected by a rod F to the plunger 1) having an adjustable end D whichis adapt ed to engage with the projections on the disc arms at the endof the in-waidstroke to move the spinning down discs out of contact withthe core and to maintain then'l in this position during the returnstroke.

The base C 'on which the spinning-down mechanism is mounted may be,positioned below the axis of the core spindle and it may be so inclinedthat the spinning down discs reciprocate in a radial path at an angle ofabout 45 degrees to the vertical. y

Instead of using single spinning down discs .at each side of the coretwo discs for example a spinning down disc and a driving disc asdescribed in the specification of my application No. 526,091, 'fi'ledDece1nber31st, 1921 may be caused to travel along" each side of the corethe reciprocating imeans hereinbefore described.

z ters Patent of the United States is 1. Spinning down mechanism fortire making machines comprising a reciprocating carriage, arms pivotallymounted on the earriage discs carried by said arms and adapted to act onthe plies of the tire as the carriage moves forward, and means movablewith the carriage and adapted at the end of each forward movementthereof to have an additional movement in the directionof the line oftravel of the carriage to effect relative movement between the carriageand said arms to move the discs away from the casing plies and retainthem in an inoperative position during return movement of the carriage.

2. Spinning down mechanism for tire making machines comprisingareciprocatoryearriage, arms pivoted on said carriage, spinning downdiscs carried by said arms, means movable with the carriage and adaptedat the end of each forward movement thereof to have an additionalmovement in the direction of the line of travel oi the carriage formoving the arms and discs into an inoperative position, and adrivingshatt adapted to actuate both the means for reciprocating thecarriage and the means tor moving the arms and discs into inoperativeposition. Y i

3. Spinning down mechanism for tire making machines comprising areciprocatory carriage, arms pivotally mounted on said carriage,spinning down discs carried by said arms, members for reciprocating thecarriage, plunger-like means adapted to effeet movement of the pivotedarms to carry the discs to inoperative position, and re ciprocatingmembers for actuating the plunger-like means at the end of each forwardmovement of the carriage, for the purpose described. a

4. Spinning down mechanism for case making machines as set'forth inclaim 1 in which aplunger or rod for engaging with the arms carrying thespinning down discs moves with the carriage until it reaches the end ofits inward stroke, whereupon relative movement between said plunger orrods and the slide takes place so that the arms carrying the spinningdown discs are moved into the inoperative position substantially asdeseribedjfor the purpose specified.

5. Spinning down mechanism for tire making machines comprising areciprocating carriage, arms pivotally mounted on the carriage, spinningdown discs carried by said arms and adapted to act on the plies of thethe as the carriage moves forward, a plunger engaging the arms earryinthe spinning down discs, said plunger adapted to move with the carriageuntil itreaches the end of its inward stroke, whereupon relativemovement between said plunger and the carriage takes place, so that thearms carrying the spinning down disc are moved into inoperativeposition, an oscillatory lever actuated by a crank discior impartingreciprocating motion to the carriage, and asecond oscillatory lever forengaging said plunger and operatively associatedwith said firstmentioned lever.

6; Spinning down mechanism for tire making machines comprising areciprocatory carriage, arms pivotally mounted on said earriage,spinningdown discs carried by said arms, and means movable with thecarriage and adaptedat the end of each forward movement thereof to havean additional movement in the direction of the line of travel ofthecarriage for reciprocating the carriage at a variable speed, the partsbeing so proportioned that during forward travel of the carriage speedincreases rapidly to the mechanism and then gradually decreases duringthe travel of the discs along the sides of the tire casing toward thebeads over which the discs t'avcl slowly.

7. Spinning down mechanism for tire making machines comprising areciprocatory carriage, arms pivotally mounted on said carriage,spinning down discs carried by said arms, an oscillatory lever forlGClPlOCfllling the carriage, a revolving member for oscillatingsaidlever, a second oscillatory lever actuated by said revolving member,aplun er slidably inonnted on the carriage and connected to the secondoscillatory lever, and means whereby the plunger will engageithe pivoteddisc carryingarms at the end of the operative stroke of the carriage soas to move the discs into an inope 'ative position. 8. Spinning downmechanism for tire making machines'as set ii'orth in claim 7, in whichthe oscillatory lever for reciprocating the carriage is provided with acam surface, an eccentrically mounted projection on the revolving memberengaging said cam surface, the latter being so shaped that a variablespeed is imparted to the spinning down discs and carriage during forwardmove ment of the latter.

9. Spinning down mechanism for tire making machines comprising areciprocatory carriage, arms pivotally mounted on said carriage,spinning down discs carried by said arms, a rotary shaft, crank oreccentric like means operated by said shaft for reciprocating thecarriage, reciprocating means on the carriage adapted to co-operate withthe pivoted disccarrying arniis to move said arms and discs into aninoperative position, and means operated by said shaft for actuating thelast said means at theend of the ope tive or forward stroke 01' thecarriage.

COLIN MAOBETH.

